Karmakar Saswata, Hrdlicka Patrick J
University of Idaho, Department of Chemistry, Moscow, ID 83844-2343, USA.
Chem Sci. 2013 Sep 1;4(9):3447-3454. doi: 10.1039/C3SC50726B.
Detection of nucleic acids using fluorophore-modified oligonucleotides forms the basis of many important applications in molecular biology, genetics and medical diagnostics. Here we demonstrate that DNA strands with central segments of alternating locked nucleic acid (LNA) and 2'--(pyren-1-yl)methyluridine monomers display very large and highly mismatch-sensitive increases in fluorescence emission upon RNA hybridization, whereas corresponding "LNA-free" controls do not. Absorbance spectra strongly suggest that LNA-induced conformational tuning of flanking 2'--(pyren-1-yl)methyluridine monomers places the reporter group in the minor groove upon RNA binding, whereby pyrene-nucleobase interactions leading to quenching of fluorescence are minimized. Accordingly, these easy-to-synthesize probes are promising SNP-discriminating RNA detection probes.
使用荧光团修饰的寡核苷酸检测核酸是分子生物学、遗传学和医学诊断中许多重要应用的基础。在此我们证明，具有交替的锁核酸（LNA）和2'-（芘-1-基）甲基尿苷单体中心片段的DNA链在与RNA杂交时荧光发射有非常大且高度错配敏感的增加，而相应的“无LNA”对照则没有。吸收光谱强烈表明，LNA诱导的侧翼2'-（芘-1-基）甲基尿苷单体的构象调整使报告基团在与RNA结合时位于小沟中，从而使导致荧光猝灭的芘-核苷酸碱基相互作用最小化。因此，这些易于合成的探针是有前景的单核苷酸多态性（SNP）区分RNA检测探针。
